MUNICH – Opel has released details of an extended-range electric concept car that it will debut at the Geneva auto show on March 2.

The General Motors Co. unit said the five-door Flextreme GT/E shows how GM's extended-range electric vehicle technology can also be used for large or mid-sized vehicles.

GM plans to launch two compact extended range electric cars, the Chevrolet Volt and its sister model the Opel Ampera. The Volt launches in selected U.S. markets later this year and in Europe next year. The Ampera will go on sale in Europe next year.

Frank Weber, Opel's head of product planning, said the concept's futuristic design shows the shape of things to come from Opel.

"Bold, expressive and highly efficient, it represents the product strategy we will apply to all our future vehicles, large and small, across all market segments," Weber said in a statement.

Opel said the concept's low, coupe-like proportions explore the potential for evolving Opel's new design language, which it describes as “sculptural artistry meets German precision within an envelope optimized for aerodynamic efficiency.”

Opel said the Flextreme GT/E has a battery-powered driving range of up to 60km (about 37 miles) and a total range of more than 500km.

Average fuel consumption is estimated at 1.6 liters per 100km (147 U.S. mpg), with CO2 emissions of less than 40 grams per kilometer.

Unlike a hybrid vehicle, the wheels of the Flextreme GT/E are powered at all times by electricity.

For typical journeys up to 60km, energy is supplied by a T-shaped lithium-ion battery pack located under the floor and rear seat.

A small gasoline engine/generator provides electricity whenever the battery's supply becomes depleted, extending the range to more than 500km until the plug-in battery pack can be recharged or the car is refueled.

The Chevy Volt will finally be going to market at the end of this year after what's become the most exhausting public development cycle in automotive history. But, it'll still be hampered by one thing: It's not particularly fetching. Frankly the Volt looks like every other drag-reducing egg-mobile — from the Prius and Insight to an extended-range electric egg like the Volt.

GM's invested a tremendous amount of money in the program and you better believe the T-shaped battery pack and motor-generator will go into other products to justify the cost, but just because it's whiz-bang tech doesn't mean the cars they go in shouldn't look good.

That's where the Flextreme GT/E concept comes in. It's packing a whole lot more eye candy than the Volt, with a sweeping roof line and an aggressive nose that reminds us of the not-C7-Corvette Stingray Concept. It's also wearing a variation of the new Opel Meriva's rear hinged rear doors for a bit more style. It's a bigger chassis but more importantly it's a heck of a lot more powerful with 273 lb-ft of torque versus the Volt's 173 lb-ft. The concept will debut at the Geneva Motor Show and knowing GM and the Volt program, hit the road sometime around 2025.